The invention relates to a process for preparing nanoparticles of a catalyst for cathodic reduction and which is tolerant to methanol, these nanoparticles comprising a metallic center and a submonolayer of a chalcogen.

A composite active material particle that can reduce battery resistance when used in an all-solid-state lithium ion battery is disclosed. The composite active material particle comprises: an active material particle; and a lithium ion conducting oxide with which at least part of a surface of the active material particle is coated, wherein the moisture content in the composite active material particle is no more than 319 ppm.

Novel active supports, novel catalysts, and methods of preparing active supports using a sacrificial template particles and methods of preparing the same are all described.

A membrane electrode assembly includes an electrolyte membrane stacked between different electrodes, wherein an ionomer layer of the electrolyte membrane comprises an adjacent electrode, a first layer having at least a same cross-sectional area as that of the adjacent electrode, a reinforcing layer and a second layer stacked at a side of the first layer, the second layer having at least the same cross-sectional area as that of the reinforcing layer.

A free-standing electrically conductive porous structure suitable to be used as a cathode of a battery, including an electrically conductive porous substrate with sulfur diffused into the electrically conductive porous substrate to create a substantially uniform layer of sulfur on a surface of the electrically conductive porous substrate. The free-standing electrically conductive porous structure has a high performance when used in a rechargeable battery. A method of manufacturing the electrically conductive porous structure is also provided.

The present invention provides a catalyst electrode for oxygen evolution comprising an electrode current collector comprising a carbon fiber fabric, a nanowire layer comprising a metal oxide-based porous nanowire grown radially from the surface of the carbon fiber, and a porous carbon coating layer disposed around the outer surface of the nanowire, thereby maximizing the specific surface area and increasing the electron transfer rate, and thus exhibiting an excellent catalytic activity for oxygen evolution reaction, and a preparation method thereof.

A method for manufacturing a metal gas diffusion layer made of a metal porous body, the method includes forming a conductive layer of carbon film layer on the metal porous body, and forming a water-repellent layer on the metal porous body formed with the conductive layer. The forming a water-repellent layer includes coating a solution containing a fluorine resin which constitutes the water-repellent layer and a volatile component which does not constitute the water-repellent layer on the metal porous body, and heat-treating the metal porous body coated with the solution at or above a temperature at which a component which contains the volatile component and which does not constitute the water-repellent layer contained in the solution and less than a temperature at which an electrical resistance of the conductive layer is increased and electron conductivity is deteriorated to thereby form the water-repellent layer composed of the fluorine resin.

An electrode active material includes: a core active material having a layered structure and capable of reversibly incorporating and deincorporating lithium; a dopant including boron and a first metal element, wherein the dopant is in the core active material; and a nanostructure disposed on a surface of the core active material and including a metal borate compound including a second metal element, wherein the second metal element is the same as the first metal element.

Techniques for preparing an electrocatalyst include growing and immobilizing an earth-abundant metal on an MXene two-dimensional (2D) substrate using a solvothermal, hydrothermal, or electrodeposition process. The earth-abundant metal may include NiFeOOH. The earth-abundant metal may include Mn, Fe, Co, Ni, Cu, Ti, V, Cr, and a combination thereof. The earth-abundant metal may be nanoparticles. The nanoparticles may include multiple metals. The electrocatalyst may be provided for an oxygen evolution reaction. The electrocatalyst may produce a current density of 500-1000 mA/cm.sup.2 for at least 20 hours without degradation thereof.

A fuel cell system includes a first fuel cell having an electrode area made of first electrode material, and a second fuel cell having an electrode area made of second electrode material having low durability against output voltage variation in comparison with the first electrode material. The fuel cell system is configured to supply electrical power to a motor generator. The fuel cell system includes a required electrical power acquisition unit configured to obtain required electrical power of the motor generator, and a control unit configured to control the second fuel cell in a manner that a variation of output electrical power of the second fuel cell becomes not more than a predetermined limit variation, and control the first fuel cell in accordance with the required electrical power and output electrical power of the second fuel cell.